The present invention relates to a screwdriver, and more particularly to a screwdriver for operating self-tightening screw. The screwdriver is able to first nail the self-tightening screw into a screwing position of a work piece and then further screw the self-tightening screw into the work piece.
In a DIY product, self-tightening screws are often used to connect work pieces with each other, such as wooden slats.
The self-tightening screw is driven by a screwdriver to screw into a work piece. Prior to screwing the self-tightening screw, the tip of the self-tightening screw must be first nailed into the work piece. There are generally two measures for nailing the tip of the self-tightening screw into the work piece. One is to use a hammering tool to strike and nail the self-tightening screw in to the work piece. The other is to directly use the screwdriver to exert an axial force onto the self-tightening screw and simultaneously drive the self-tightening screw into the work piece. With respect to the first measure, an operator must pinch the self-tightening screw with one hand and at the same time operate the hammering tool to strike the self-tightening screw with the other hand so as to nail the self-tightening screw into the work piece. During the striking operation, it often takes place that the hammering tool incautiously hits and injures the hand pinching the self-tightening screw. With respect to the second measure, the pressure exerted by the operator onto the self-tightening screw is not so direct and effective as the pressure produced by the hammering tool so that it is laborious for the operator to effectively press the self-tightening screw against the work piece. Moreover, the tip of the self-tightening screw contacts with the work piece at a point with small area so that the self-tightening screw contacts with the work piece in an unstable state and tends to deflect and can be hardly located on the work piece. Therefore, during operation, it often takes place that the screwdriver slips away from the self-tightening screw and the self-tightening screw bounds away to other place. Therefore, it is necessary to repeat the operation many times for nailing the self-tightening screw into the work piece.
It is therefore a primary object of the present invention to provide a screwdriver for operating self-tightening screw. The screwdriver is able to first nail the self-tightening screw into a work piece to facilitate the screwing of the self-tightening screw.
It is a further object of the present invention to provide a screwdriver for operating self-tightening screw, which is able to first nail the self-tightening screw into work piece without using any other tool and pinching the screw with a hand so that the user""s hand is protected from being hit and injured.
It is still a further object of the present invention to provide a screwdriver for operating self-tightening screw, by which during the nailing of the self-tightening screw, the screw will not deflect or randomly bound away.
It is still a further object of the present invention to provide a screwdriver for operating self-tightening screw, which enables a user to quickly and conveniently nail a self-tightening screw.
The present invention can be best understood through the following description and accompanying drawings wherein: